A Novel High-Sensitivity Butterfly Gyroscope Driven by Horizontal Driving Force

Abstract

Sensitivity is an important performance index of micro-machined gyroscope, and driving amplitude and initial capacitance gap are related to the signal-noise ratio as well as the sensitivity of gyroscope. The traditional butterfly gyroscope in our research group will generate both horizontal and vertical driving amplitude when driven in driving mode. So, the signal-to-noise ratio is subjected to the vertical driving displacement and initial capacitance gap, which, to a great extent, limits its sensitivity. In this paper, a novel high-sensitivity butterfly gyroscope with rectangle vibration beam was proposed, which will generate almost only horizontal displacement due to the structural characteristics when driven by horizontal driving force. Therefore, the proposed structure can not only increase the driving amplitude, but also reduce the initial capacitance gap, so as to enhance the signal-noise ratio as well as sensitivity of the gyroscope. After the structural design and manufacture processing, the performance of the proposed butterfly gyroscope was tested, and the angle random walk is measured to be $1.244\textrm {deg}/\surd \textrm {h}$ , and the bias stability reached 3.58deg/h.